EDIT THIS FILE WITH CAUTION (/tmp/.ag-2caiQA/ag-bdaaPA)
It has been AutoGen-ed August 14, 2018 at 08:28:54 AM by AutoGen 5.18.5
From the definitions ntp.conf.def
and the template file agman-cmd.tpl
Following these is a section describing Miscellaneous\f[] Options\f[]. While there is a rich set of options available, the only required option is one or more \f\*[B-Font]pool\f[], \f\*[B-Font]server\f[], \f\*[B-Font]peer\f[], \f\*[B-Font]broadcast\f[] or \f\*[B-Font]manycastclient\f[] commands.
7 .NOP \f\*[B-Font]pool\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]burst\f[]] [\f\*[B-Font]iburst\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]]
7 .NOP \f\*[B-Font]server\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]burst\f[]] [\f\*[B-Font]iburst\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] [\f\*[B-Font]true\f[]]
7 .NOP \f\*[B-Font]peer\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] [\f\*[B-Font]true\f[]] [\f\*[B-Font]xleave\f[]]
7 .NOP \f\*[B-Font]broadcast\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]ttl\f[] \f\*[I-Font]ttl\f[]] [\f\*[B-Font]xleave\f[]]
7 .NOP \f\*[B-Font]manycastclient\f[] \f\*[I-Font]address\f[] [\f\*[B-Font]key\f[] \f\*[I-Font]key\f[] \f\*[I-Font]|\f[] \f\*[B-Font]autokey\f[]] [\f\*[B-Font]version\f[] \f\*[I-Font]version\f[]] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[]] [\f\*[B-Font]ttl\f[] \f\*[I-Font]ttl\f[]]
These five commands specify the time server name or address to be used and the mode in which to operate. The \f\*[I-Font]address\f[] can be either a DNS name or an IP address in dotted-quad notation. Additional information on association behavior can be found in the "Association Management" page (available as part of the HTML documentation provided in /usr/share/doc/ntp\f[]).
7 .NOP \f\*[B-Font]pool\f[] For type s addresses, this command mobilizes a persistent client mode association with a number of remote servers. In this mode the local clock can synchronized to the remote server, but the remote server can never be synchronized to the local clock.
7 .NOP \f\*[B-Font]server\f[] For type s and r addresses, this command mobilizes a persistent client mode association with the specified remote server or local radio clock. In this mode the local clock can synchronized to the remote server, but the remote server can never be synchronized to the local clock. This command should not\f[] be used for type b or m addresses.
7 .NOP \f\*[B-Font]peer\f[] For type s addresses (only), this command mobilizes a persistent symmetric-active mode association with the specified remote peer. In this mode the local clock can be synchronized to the remote peer or the remote peer can be synchronized to the local clock. This is useful in a network of servers where, depending on various failure scenarios, either the local or remote peer may be the better source of time. This command should NOT be used for type b, m or r addresses.
7 .NOP \f\*[B-Font]broadcast\f[] For type b and m addresses (only), this command mobilizes a persistent broadcast mode association. Multiple commands can be used to specify multiple local broadcast interfaces (subnets) and/or multiple multicast groups. Note that local broadcast messages go only to the interface associated with the subnet specified, but multicast messages go to all interfaces. In broadcast mode the local server sends periodic broadcast messages to a client population at the \f\*[I-Font]address\f[] specified, which is usually the broadcast address on (one of) the local network(s) or a multicast address assigned to NTP. The IANA has assigned the multicast group address IPv4 224.0.1.1 and IPv6 ff05::101 (site local) exclusively to NTP, but other nonconflicting addresses can be used to contain the messages within administrative boundaries. Ordinarily, this specification applies only to the local server operating as a sender; for operation as a broadcast client, see the \f\*[B-Font]broadcastclient\f[] or \f\*[B-Font]multicastclient\f[] commands below.
7 .NOP \f\*[B-Font]manycastclient\f[] For type m addresses (only), this command mobilizes a manycast client mode association for the multicast address specified. In this case a specific address must be supplied which matches the address used on the \f\*[B-Font]manycastserver\f[] command for the designated manycast servers. The NTP multicast address 224.0.1.1 assigned by the IANA should NOT be used, unless specific means are taken to avoid spraying large areas of the Internet with these messages and causing a possibly massive implosion of replies at the sender. The \f\*[B-Font]manycastserver\f[] command specifies that the local server is to operate in client mode with the remote servers that are discovered as the result of broadcast/multicast messages. The client broadcasts a request message to the group address associated with the specified \f\*[I-Font]address\f[] and specifically enabled servers respond to these messages. The client selects the servers providing the best time and continues as with the \f\*[B-Font]server\f[] command. The remaining servers are discarded as if never heard.
Options:
7 .NOP \f\*[B-Font]autokey\f[] All packets sent to and received from the server or peer are to include authentication fields encrypted using the autokey scheme described in Authentication\f[] Options\f[].
7 .NOP \f\*[B-Font]burst\f[] when the server is reachable, send a burst of eight packets instead of the usual one. The packet spacing is normally 2 s; however, the spacing between the first and second packets can be changed with the \f\*[B-Font]calldelay\f[] command to allow additional time for a modem or ISDN call to complete. This is designed to improve timekeeping quality with the \f\*[B-Font]server\f[] command and s addresses.
7 .NOP \f\*[B-Font]iburst\f[] When the server is unreachable, send a burst of eight packets instead of the usual one. The packet spacing is normally 2 s; however, the spacing between the first two packets can be changed with the \f\*[B-Font]calldelay\f[] command to allow additional time for a modem or ISDN call to complete. This is designed to speed the initial synchronization acquisition with the \f\*[B-Font]server\f[] command and s addresses and when ntpd\f[](@NTPD_MS@)\f[] is started with the \f\*[B-Font]-q\f[] option.
7 .NOP \f\*[B-Font]key\f[] \f\*[I-Font]key\f[] All packets sent to and received from the server or peer are to include authentication fields encrypted using the specified \f\*[I-Font]key\f[] identifier with values from 1 to 65535, inclusive. The default is to include no encryption field.
7 .NOP \f\*[B-Font]minpoll\f[] \f\*[I-Font]minpoll\f[]
7 .NOP \f\*[B-Font]maxpoll\f[] \f\*[I-Font]maxpoll\f[] These options specify the minimum and maximum poll intervals for NTP messages, as a power of 2 in seconds The maximum poll interval defaults to 10 (1,024 s), but can be increased by the \f\*[B-Font]maxpoll\f[] option to an upper limit of 17 (36.4 h). The minimum poll interval defaults to 6 (64 s), but can be decreased by the \f\*[B-Font]minpoll\f[] option to a lower limit of 4 (16 s).
7 .NOP \f\*[B-Font]noselect\f[] Marks the server as unused, except for display purposes. The server is discarded by the selection algroithm.
7 .NOP \f\*[B-Font]preempt\f[] Says the association can be preempted.
7 .NOP \f\*[B-Font]true\f[] Marks the server as a truechimer. Use this option only for testing.
7 .NOP \f\*[B-Font]prefer\f[] Marks the server as preferred. All other things being equal, this host will be chosen for synchronization among a set of correctly operating hosts. See the "Mitigation Rules and the prefer Keyword" page (available as part of the HTML documentation provided in /usr/share/doc/ntp\f[]) for further information.
7 .NOP \f\*[B-Font]true\f[] Forces the association to always survive the selection and clustering algorithms. This option should almost certainly only\f[] be used while testing an association.
7 .NOP \f\*[B-Font]ttl\f[] \f\*[I-Font]ttl\f[] This option is used only with broadcast server and manycast client modes. It specifies the time-to-live \f\*[I-Font]ttl\f[] to use on broadcast server and multicast server and the maximum \f\*[I-Font]ttl\f[] for the expanding ring search with manycast client packets. Selection of the proper value, which defaults to 127, is something of a black art and should be coordinated with the network administrator.
7 .NOP \f\*[B-Font]version\f[] \f\*[I-Font]version\f[] Specifies the version number to be used for outgoing NTP packets. Versions 1-4 are the choices, with version 4 the default.
7 .NOP \f\*[B-Font]xleave\f[] Valid in \f\*[B-Font]peer\f[] and \f\*[B-Font]broadcast\f[] modes only, this flag enables interleave mode.
7 .NOP \f\*[B-Font]broadcastclient\f[] This command enables reception of broadcast server messages to any local interface (type b) address. Upon receiving a message for the first time, the broadcast client measures the nominal server propagation delay using a brief client/server exchange with the server, then enters the broadcast client mode, in which it synchronizes to succeeding broadcast messages. Note that, in order to avoid accidental or malicious disruption in this mode, both the server and client should operate using symmetric-key or public-key authentication as described in Authentication\f[] Options\f[].
7 .NOP \f\*[B-Font]manycastserver\f[] \f\*[I-Font]address\f[] \f\*[I-Font]...\f[] This command enables reception of manycast client messages to the multicast group address(es) (type m) specified. At least one address is required, but the NTP multicast address 224.0.1.1 assigned by the IANA should NOT be used, unless specific means are taken to limit the span of the reply and avoid a possibly massive implosion at the original sender. Note that, in order to avoid accidental or malicious disruption in this mode, both the server and client should operate using symmetric-key or public-key authentication as described in Authentication\f[] Options\f[].
7 .NOP \f\*[B-Font]multicastclient\f[] \f\*[I-Font]address\f[] \f\*[I-Font]...\f[] This command enables reception of multicast server messages to the multicast group address(es) (type m) specified. Upon receiving a message for the first time, the multicast client measures the nominal server propagation delay using a brief client/server exchange with the server, then enters the broadcast client mode, in which it synchronizes to succeeding multicast messages. Note that, in order to avoid accidental or malicious disruption in this mode, both the server and client should operate using symmetric-key or public-key authentication as described in Authentication\f[] Options\f[].
7 .NOP \f\*[B-Font]mdnstries\f[] \f\*[I-Font]number\f[] If we are participating in mDNS, after we have synched for the first time we attempt to register with the mDNS system. If that registration attempt fails, we try again at one minute intervals for up to \f\*[B-Font]mdnstries\f[] times. After all, \f\*[B-Font]ntpd\f[] may be starting before mDNS. The default value for \f\*[B-Font]mdnstries\f[] is 5.
The cryptographic means necessary for all Autokey operations
is provided by the OpenSSL software library.
This library is available from http://www.openssl.org/
and can be installed using the procedures outlined
in the Building and Installing the Distribution page.
Once installed,
the configure and build
process automatically detects the library and links
the library routines required.
The Autokey protocol has several modes of operation corresponding to the various NTP modes supported. Most modes use a special cookie which can be computed independently by the client and server, but encrypted in transmission. All modes use in addition a variant of the S-KEY scheme, in which a pseudo-random key list is generated and used in reverse order. These schemes are described along with an executive summary, current status, briefing slides and reading list on the Autonomous\f[] Authentication\f[] page. The specific cryptographic environment used by Autokey servers and clients is determined by a set of files and soft links generated by the ntp-keygen\f[](1ntpkeygenmdoc)\f[] program. This includes a required host key file, required certificate file and optional sign key file, leapsecond file and identity scheme files. The digest/signature scheme is specified in the X.509 certificate along with the matching sign key. There are several schemes available in the OpenSSL software library, each identified by a specific string such as \f\*[B-Font]md5WithRSAEncryption\f[], which stands for the MD5 message digest with RSA encryption scheme. The current NTP distribution supports all the schemes in the OpenSSL library, including those based on RSA and DSA digital signatures. NTP secure groups can be used to define cryptographic compartments and security hierarchies. It is important that every host in the group be able to construct a certificate trail to one or more trusted hosts in the same group. Each group host runs the Autokey protocol to obtain the certificates for all hosts along the trail to one or more trusted hosts. This requires the configuration file in all hosts to be engineered so that, even under anticipated failure conditions, the NTP subnet will form such that every group host can find a trail to at least one trusted host.
7 .NOP \f\*[B-Font]autokey\f[] [\f\*[I-Font]logsec\f[]] Specifies the interval between regenerations of the session key list used with the Autokey protocol. Note that the size of the key list for each association depends on this interval and the current poll interval. The default value is 12 (4096 s or about 1.1 hours). For poll intervals above the specified interval, a session key list with a single entry will be regenerated for every message sent.
7 .NOP \f\*[B-Font]controlkey\f[] \f\*[I-Font]key\f[] Specifies the key identifier to use with the ntpq\f[](@NTPQ_MS@)\f[] utility, which uses the standard protocol defined in RFC-1305. The \f\*[I-Font]key\f[] argument is the key identifier for a trusted key, where the value can be in the range 1 to 65,535, inclusive.
7 .NOP \f\*[B-Font]crypto\f[] [\f\*[B-Font]cert\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]leap\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]randfile\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]host\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]sign\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]gq\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]gqpar\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]iffpar\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]mvpar\f[] \f\*[I-Font]file\f[]] [\f\*[B-Font]pw\f[] \f\*[I-Font]password\f[]] This command requires the OpenSSL library. It activates public key cryptography, selects the message digest and signature encryption scheme and loads the required private and public values described above. If one or more files are left unspecified, the default names are used as described above. Unless the complete path and name of the file are specified, the location of a file is relative to the keys directory specified in the \f\*[B-Font]keysdir\f[] command or default /usr/local/etc\f[]. Following are the subcommands:
7 .NOP \f\*[B-Font]cert\f[] \f\*[I-Font]file\f[] Specifies the location of the required host public certificate file. This overrides the link ntpkey_cert_\f[]\f\*[I-Font]hostname\f[] in the keys directory.
7 .NOP \f\*[B-Font]gqpar\f[] \f\*[I-Font]file\f[] Specifies the location of the optional GQ parameters file. This overrides the link ntpkey_gq_\f[]\f\*[I-Font]hostname\f[] in the keys directory.
7 .NOP \f\*[B-Font]host\f[] \f\*[I-Font]file\f[] Specifies the location of the required host key file. This overrides the link ntpkey_key_\f[]\f\*[I-Font]hostname\f[] in the keys directory.
7 .NOP \f\*[B-Font]iffpar\f[] \f\*[I-Font]file\f[] Specifies the location of the optional IFF parameters file. This overrides the link ntpkey_iff_\f[]\f\*[I-Font]hostname\f[] in the keys directory.
7 .NOP \f\*[B-Font]leap\f[] \f\*[I-Font]file\f[] Specifies the location of the optional leapsecond file. This overrides the link ntpkey_leap\f[] in the keys directory.
7 .NOP \f\*[B-Font]mvpar\f[] \f\*[I-Font]file\f[] Specifies the location of the optional MV parameters file. This overrides the link ntpkey_mv_\f[]\f\*[I-Font]hostname\f[] in the keys directory.
7 .NOP \f\*[B-Font]pw\f[] \f\*[I-Font]password\f[] Specifies the password to decrypt files containing private keys and identity parameters. This is required only if these files have been encrypted.
7 .NOP \f\*[B-Font]randfile\f[] \f\*[I-Font]file\f[] Specifies the location of the random seed file used by the OpenSSL library. The defaults are described in the main text above.
7 .NOP \f\*[B-Font]sign\f[] \f\*[I-Font]file\f[] Specifies the location of the optional sign key file. This overrides the link ntpkey_sign_\f[]\f\*[I-Font]hostname\f[] in the keys directory. If this file is not found, the host key is also the sign key.
7 .NOP \f\*[B-Font]keys\f[] \f\*[I-Font]keyfile\f[] Specifies the complete path and location of the MD5 key file containing the keys and key identifiers used by ntpd\f[](@NTPD_MS@)\f[], ntpq\f[](@NTPQ_MS@)\f[] and ntpdc\f[](@NTPDC_MS@)\f[] when operating with symmetric key cryptography. This is the same operation as the \f\*[B-Font]-k\f[] command line option.
7 .NOP \f\*[B-Font]keysdir\f[] \f\*[I-Font]path\f[] This command specifies the default directory path for cryptographic keys, parameters and certificates. The default is /usr/local/etc/\f[].
7 .NOP \f\*[B-Font]requestkey\f[] \f\*[I-Font]key\f[] Specifies the key identifier to use with the ntpdc\f[](@NTPDC_MS@)\f[] utility program, which uses a proprietary protocol specific to this implementation of ntpd\f[](@NTPD_MS@)\f[]. The \f\*[I-Font]key\f[] argument is a key identifier for the trusted key, where the value can be in the range 1 to 65,535, inclusive.
7 .NOP \f\*[B-Font]revoke\f[] \f\*[I-Font]logsec\f[] Specifies the interval between re-randomization of certain cryptographic values used by the Autokey scheme, as a power of 2 in seconds. These values need to be updated frequently in order to deflect brute-force attacks on the algorithms of the scheme; however, updating some values is a relatively expensive operation. The default interval is 16 (65,536 s or about 18 hours). For poll intervals above the specified interval, the values will be updated for every message sent.
7 .NOP \f\*[B-Font]trustedkey\f[] \f\*[I-Font]key\f[] \f\*[I-Font]...\f[] Specifies the key identifiers which are trusted for the purposes of authenticating peers with symmetric key cryptography, as well as keys used by the ntpq\f[](@NTPQ_MS@)\f[] and ntpdc\f[](@NTPDC_MS@)\f[] programs. The authentication procedures require that both the local and remote servers share the same key and key identifier for this purpose, although different keys can be used with different servers. The \f\*[I-Font]key\f[] arguments are 32-bit unsigned integers with values from 1 to 65,535.
7 .NOP 101 (bad field format or length) The packet has invalid version, length or format.
7 .NOP 102 (bad timestamp) The packet timestamp is the same or older than the most recent received. This could be due to a replay or a server clock time step.
7 .NOP 103 (bad filestamp) The packet filestamp is the same or older than the most recent received. This could be due to a replay or a key file generation error.
7 .NOP 104 (bad or missing public key) The public key is missing, has incorrect format or is an unsupported type.
7 .NOP 105 (unsupported digest type) The server requires an unsupported digest/signature scheme.
7 .NOP 106 (mismatched digest types) Not used.
7 .NOP 107 (bad signature length) The signature length does not match the current public key.
7 .NOP 108 (signature not verified) The message fails the signature check. It could be bogus or signed by a different private key.
7 .NOP 109 (certificate not verified) The certificate is invalid or signed with the wrong key.
7 .NOP 110 (certificate not verified) The certificate is not yet valid or has expired or the signature could not be verified.
7 .NOP 111 (bad or missing cookie) The cookie is missing, corrupted or bogus.
7 .NOP 112 (bad or missing leapseconds table) The leapseconds table is missing, corrupted or bogus.
7 .NOP 113 (bad or missing certificate) The certificate is missing, corrupted or bogus.
7 .NOP 114 (bad or missing identity) The identity key is missing, corrupt or bogus.
7 .NOP \f\*[B-Font]statistics\f[] \f\*[I-Font]name\f[] \f\*[I-Font]...\f[] Enables writing of statistics records. Currently, eight kinds of \f\*[I-Font]name\f[] statistics are supported.
7 .NOP \f\*[B-Font]clockstats\f[] Enables recording of clock driver statistics information. Each update received from a clock driver appends a line of the following form to the file generation set named \f\*[B-Font]clockstats\f[]:
49213 525.624 127.127.4.1 93 226 00:08:29.606 DThe first two fields show the date (Modified Julian Day) and time (seconds and fraction past UTC midnight). The next field shows the clock address in dotted-quad notation. The final field shows the last timecode received from the clock in decoded ASCII format, where meaningful. In some clock drivers a good deal of additional information can be gathered and displayed as well. See information specific to each clock for further details.
7 .NOP \f\*[B-Font]cryptostats\f[] This option requires the OpenSSL cryptographic software library. It enables recording of cryptographic public key protocol information. Each message received by the protocol module appends a line of the following form to the file generation set named \f\*[B-Font]cryptostats\f[]:
49213 525.624 127.127.4.1 messageThe first two fields show the date (Modified Julian Day) and time (seconds and fraction past UTC midnight). The next field shows the peer address in dotted-quad notation, The final message field includes the message type and certain ancillary information. See the Authentication\f[] Options\f[] section for further information.
7 .NOP \f\*[B-Font]loopstats\f[] Enables recording of loop filter statistics information. Each update of the local clock outputs a line of the following form to the file generation set named \f\*[B-Font]loopstats\f[]:
50935 75440.031 0.000006019 13.778190 0.000351733 0.0133806The first two fields show the date (Modified Julian Day) and time (seconds and fraction past UTC midnight). The next five fields show time offset (seconds), frequency offset (parts per million - PPM), RMS jitter (seconds), Allan deviation (PPM) and clock discipline time constant.
7 .NOP \f\*[B-Font]peerstats\f[] Enables recording of peer statistics information. This includes statistics records of all peers of a NTP server and of special signals, where present and configured. Each valid update appends a line of the following form to the current element of a file generation set named \f\*[B-Font]peerstats\f[]:
48773 10847.650 127.127.4.1 9714 -0.001605376 0.000000000 0.001424877 0.000958674The first two fields show the date (Modified Julian Day) and time (seconds and fraction past UTC midnight). The next two fields show the peer address in dotted-quad notation and status, respectively. The status field is encoded in hex in the format described in Appendix A of the NTP specification RFC 1305. The final four fields show the offset, delay, dispersion and RMS jitter, all in seconds.
7 .NOP \f\*[B-Font]rawstats\f[] Enables recording of raw-timestamp statistics information. This includes statistics records of all peers of a NTP server and of special signals, where present and configured. Each NTP message received from a peer or clock driver appends a line of the following form to the file generation set named \f\*[B-Font]rawstats\f[]:
50928 2132.543 128.4.1.1 128.4.1.20 3102453281.584327000 3102453281.58622800031 02453332.540806000 3102453332.541458000The first two fields show the date (Modified Julian Day) and time (seconds and fraction past UTC midnight). The next two fields show the remote peer or clock address followed by the local address in dotted-quad notation. The final four fields show the originate, receive, transmit and final NTP timestamps in order. The timestamp values are as received and before processing by the various data smoothing and mitigation algorithms.
7 .NOP \f\*[B-Font]sysstats\f[] Enables recording of ntpd statistics counters on a periodic basis. Each hour a line of the following form is appended to the file generation set named \f\*[B-Font]sysstats\f[]:
50928 2132.543 36000 81965 0 9546 56 71793 512 540 10 147The first two fields show the date (Modified Julian Day) and time (seconds and fraction past UTC midnight). The remaining ten fields show the statistics counter values accumulated since the last generated line.
7 .NOP Time since restart \f\*[B-Font]36000\f[] Time in hours since the system was last rebooted.
7 .NOP Packets received \f\*[B-Font]81965\f[] Total number of packets received.
7 .NOP Packets processed \f\*[B-Font]0\f[] Number of packets received in response to previous packets sent
7 .NOP Current version \f\*[B-Font]9546\f[] Number of packets matching the current NTP version.
7 .NOP Previous version \f\*[B-Font]56\f[] Number of packets matching the previous NTP version.
7 .NOP Bad version \f\*[B-Font]71793\f[] Number of packets matching neither NTP version.
7 .NOP Access denied \f\*[B-Font]512\f[] Number of packets denied access for any reason.
7 .NOP Bad length or format \f\*[B-Font]540\f[] Number of packets with invalid length, format or port number.
7 .NOP Bad authentication \f\*[B-Font]10\f[] Number of packets not verified as authentic.
7 .NOP Rate exceeded \f\*[B-Font]147\f[] Number of packets discarded due to rate limitation.
7 .NOP \f\*[B-Font]statsdir\f[] \f\*[I-Font]directory_path\f[] Indicates the full path of a directory where statistics files should be created (see below). This keyword allows the (otherwise constant) \f\*[B-Font]filegen\f[] filename prefix to be modified for file generation sets, which is useful for handling statistics logs.
7 .NOP \f\*[B-Font]filegen\f[] \f\*[I-Font]name\f[] [\f\*[B-Font]file\f[] \f\*[I-Font]filename\f[]] [\f\*[B-Font]type\f[] \f\*[I-Font]typename\f[]] [\f\*[B-Font]link\f[] | \f\*[B-Font]nolink\f[]] [\f\*[B-Font]enable\f[] | \f\*[B-Font]disable\f[]] Configures setting of generation file set name. Generation file sets provide a means for handling files that are continuously growing during the lifetime of a server. Server statistics are a typical example for such files. Generation file sets provide access to a set of files used to store the actual data. At any time at most one element of the set is being written to. The type given specifies when and how data will be directed to a new element of the set. This way, information stored in elements of a file set that are currently unused are available for administrational operations without the risk of disturbing the operation of ntpd. (Most important: they can be removed to free space for new data produced.) Note that this command can be sent from the ntpdc\f[](@NTPDC_MS@)\f[] program running at a remote location.
7 .NOP \f\*[B-Font]name\f[] This is the type of the statistics records, as shown in the \f\*[B-Font]statistics\f[] command.
7 .NOP \f\*[B-Font]file\f[] \f\*[I-Font]filename\f[] This is the file name for the statistics records. Filenames of set members are built from three concatenated elements \f\*[B-Font]prefix\f[], \f\*[B-Font]filename\f[] and \f\*[B-Font]suffix\f[]:
7 .NOP \f\*[B-Font]prefix\f[] This is a constant filename path. It is not subject to modifications via the \f\*[I-Font]filegen\f[] option. It is defined by the server, usually specified as a compile-time constant. It may, however, be configurable for individual file generation sets via other commands. For example, the prefix used with \f\*[I-Font]loopstats\f[] and \f\*[I-Font]peerstats\f[] generation can be configured using the \f\*[I-Font]statsdir\f[] option explained above.
7 .NOP \f\*[B-Font]filename\f[] This string is directly concatenated to the prefix mentioned above (no intervening \[oq]/\[cq]). This can be modified using the file argument to the \f\*[I-Font]filegen\f[] statement. No ..\f[] elements are allowed in this component to prevent filenames referring to parts outside the filesystem hierarchy denoted by \f\*[I-Font]prefix\f[].
7 .NOP \f\*[B-Font]suffix\f[] This part is reflects individual elements of a file set. It is generated according to the type of a file set.
7 .NOP \f\*[B-Font]type\f[] \f\*[I-Font]typename\f[] A file generation set is characterized by its type. The following types are supported:
7 .NOP \f\*[B-Font]none\f[] The file set is actually a single plain file.
7 .NOP \f\*[B-Font]pid\f[] One element of file set is used per incarnation of a ntpd server. This type does not perform any changes to file set members during runtime, however it provides an easy way of separating files belonging to different ntpd\f[](@NTPD_MS@)\f[] server incarnations. The set member filename is built by appending a \[oq].\[cq] to concatenated \f\*[I-Font]prefix\f[] and \f\*[I-Font]filename\f[] strings, and appending the decimal representation of the process ID of the ntpd\f[](@NTPD_MS@)\f[] server process.
7 .NOP \f\*[B-Font]day\f[] One file generation set element is created per day. A day is defined as the period between 00:00 and 24:00 UTC. The file set member suffix consists of a \[oq].\[cq] and a day specification in the form \f\*[B-Font]YYYYMMdd\f[]. \f\*[B-Font]YYYY\f[] is a 4-digit year number (e.g., 1992). \f\*[B-Font]MM\f[] is a two digit month number. \f\*[B-Font]dd\f[] is a two digit day number. Thus, all information written at 10 December 1992 would end up in a file named \f\*[I-Font]prefix\f[] \f\*[I-Font]filename\f[].19921210.
7 .NOP \f\*[B-Font]week\f[] Any file set member contains data related to a certain week of a year. The term week is defined by computing day-of-year modulo 7. Elements of such a file generation set are distinguished by appending the following suffix to the file set filename base: A dot, a 4-digit year number, the letter \f\*[B-Font]W\f[], and a 2-digit week number. For example, information from January, 10th 1992 would end up in a file with suffix .NOP. \f\*[I-Font]1992W1\f[].
7 .NOP \f\*[B-Font]month\f[] One generation file set element is generated per month. The file name suffix consists of a dot, a 4-digit year number, and a 2-digit month.
7 .NOP \f\*[B-Font]year\f[] One generation file element is generated per year. The filename suffix consists of a dot and a 4 digit year number.
7 .NOP \f\*[B-Font]age\f[] This type of file generation sets changes to a new element of the file set every 24 hours of server operation. The filename suffix consists of a dot, the letter \f\*[B-Font]a\f[], and an 8-digit number. This number is taken to be the number of seconds the server is running at the start of the corresponding 24-hour period. Information is only written to a file generation by specifying \f\*[B-Font]enable\f[]; output is prevented by specifying \f\*[B-Font]disable\f[].
7 .NOP \f\*[B-Font]link\f[] | \f\*[B-Font]nolink\f[] It is convenient to be able to access the current element of a file generation set by a fixed name. This feature is enabled by specifying \f\*[B-Font]link\f[] and disabled using \f\*[B-Font]nolink\f[]. If link is specified, a hard link from the current file set element to a file without suffix is created. When there is already a file with this name and the number of links of this file is one, it is renamed appending a dot, the letter \f\*[B-Font]C\f[], and the pid of the ntpd\f[](@NTPD_MS@)\f[] server process. When the number of links is greater than one, the file is unlinked. This allows the current file to be accessed by a constant name.
7 .NOP \f\*[B-Font]enable\f[] \f\*[B-Font]|\f[] \f\*[B-Font]disable\f[] Enables or disables the recording function.
7 .NOP \f\*[B-Font]discard\f[] [\f\*[B-Font]average\f[] \f\*[I-Font]avg\f[]] [\f\*[B-Font]minimum\f[] \f\*[I-Font]min\f[]] [\f\*[B-Font]monitor\f[] \f\*[I-Font]prob\f[]] Set the parameters of the \f\*[B-Font]limited\f[] facility which protects the server from client abuse. The \f\*[B-Font]average\f[] subcommand specifies the minimum average packet spacing, while the \f\*[B-Font]minimum\f[] subcommand specifies the minimum packet spacing. Packets that violate these minima are discarded and a kiss-o'-death packet returned if enabled. The default minimum average and minimum are 5 and 2, respectively. The \f\*[B-Font]monitor\f[] subcommand specifies the probability of discard for packets that overflow the rate-control window.
7 .NOP \f\*[B-Font]restrict\f[] \f\*[B-Font]address\f[] [\f\*[B-Font]mask\f[] \f\*[I-Font]mask\f[]] [\f\*[B-Font]ippeerlimit\f[] \f\*[I-Font]int\f[]] [\f\*[I-Font]flag\f[] \f\*[I-Font]...\f[]] The \f\*[I-Font]address\f[] argument expressed in dotted-quad form is the address of a host or network. Alternatively, the \f\*[I-Font]address\f[] argument can be a valid host DNS name. The \f\*[I-Font]mask\f[] argument expressed in dotted-quad form defaults to \f\*[B-Font]255.255.255.255\f[], meaning that the \f\*[I-Font]address\f[] is treated as the address of an individual host. A default entry (address \f\*[B-Font]0.0.0.0\f[], mask \f\*[B-Font]0.0.0.0\f[]) is always included and is always the first entry in the list. Note that text string \f\*[B-Font]default\f[], with no mask option, may be used to indicate the default entry. The \f\*[B-Font]ippeerlimit\f[] directive limits the number of peer requests for each IP to \f\*[I-Font]int\f[], where a value of -1 means "unlimited", the current default. A value of 0 means "none". There would usually be at most 1 peering request per IP, but if the remote peering requests are behind a proxy there could well be more than 1 per IP. In the current implementation, \f\*[B-Font]flag\f[] always restricts access, i.e., an entry with no flags indicates that free access to the server is to be given. The flags are not orthogonal, in that more restrictive flags will often make less restrictive ones redundant. The flags can generally be classed into two categories, those which restrict time service and those which restrict informational queries and attempts to do run-time reconfiguration of the server. One or more of the following flags may be specified:
7 .NOP \f\*[B-Font]ignore\f[] Deny packets of all kinds, including ntpq\f[](@NTPQ_MS@)\f[] and ntpdc\f[](@NTPDC_MS@)\f[] queries.
7 .NOP \f\*[B-Font]kod\f[] If this flag is set when an access violation occurs, a kiss-o'-death (KoD) packet is sent. KoD packets are rate limited to no more than one per second. If another KoD packet occurs within one second after the last one, the packet is dropped.
7 .NOP \f\*[B-Font]limited\f[] Deny service if the packet spacing violates the lower limits specified in the \f\*[B-Font]discard\f[] command. A history of clients is kept using the monitoring capability of ntpd\f[](@NTPD_MS@)\f[]. Thus, monitoring is always active as long as there is a restriction entry with the \f\*[B-Font]limited\f[] flag.
7 .NOP \f\*[B-Font]lowpriotrap\f[] Declare traps set by matching hosts to be low priority. The number of traps a server can maintain is limited (the current limit is 3). Traps are usually assigned on a first come, first served basis, with later trap requestors being denied service. This flag modifies the assignment algorithm by allowing low priority traps to be overridden by later requests for normal priority traps.
7 .NOP \f\*[B-Font]noepeer\f[] Deny ephemeral peer requests, even if they come from an authenticated source. Note that the ability to use a symmetric key for authentication may be restricted to one or more IPs or subnets via the third field of the ntp.keys\f[] file. This restriction is not enabled by default, to maintain backward compatability. Expect \f\*[B-Font]noepeer\f[] to become the default in ntp-4.4.
7 .NOP \f\*[B-Font]nomodify\f[] Deny ntpq\f[](@NTPQ_MS@)\f[] and ntpdc\f[](@NTPDC_MS@)\f[] queries which attempt to modify the state of the server (i.e., run time reconfiguration). Queries which return information are permitted.
7 .NOP \f\*[B-Font]noquery\f[] Deny ntpq\f[](@NTPQ_MS@)\f[] and ntpdc\f[](@NTPDC_MS@)\f[] queries. Time service is not affected.
7 .NOP \f\*[B-Font]nopeer\f[] Deny unauthenticated packets which would result in mobilizing a new association. This includes broadcast and symmetric active packets when a configured association does not exist. It also includes \f\*[B-Font]pool\f[] associations, so if you want to use servers from a \f\*[B-Font]pool\f[] directive and also want to use \f\*[B-Font]nopeer\f[] by default, you'll want a \f\*[B-Font]restrict source ...\f[] line as well that does not\f[] include the \f\*[B-Font]nopeer\f[] directive.
7 .NOP \f\*[B-Font]noserve\f[] Deny all packets except ntpq\f[](@NTPQ_MS@)\f[] and ntpdc\f[](@NTPDC_MS@)\f[] queries.
7 .NOP \f\*[B-Font]notrap\f[] Decline to provide mode 6 control message trap service to matching hosts. The trap service is a subsystem of the ntpq\f[](@NTPQ_MS@)\f[] control message protocol which is intended for use by remote event logging programs.
7 .NOP \f\*[B-Font]notrust\f[] Deny service unless the packet is cryptographically authenticated.
7 .NOP \f\*[B-Font]ntpport\f[] This is actually a match algorithm modifier, rather than a restriction flag. Its presence causes the restriction entry to be matched only if the source port in the packet is the standard NTP UDP port (123). Both \f\*[B-Font]ntpport\f[] and \f\*[B-Font]non-ntpport\f[] may be specified. The \f\*[B-Font]ntpport\f[] is considered more specific and is sorted later in the list.
7 .NOP \f\*[B-Font]version\f[] Deny packets that do not match the current NTP version.
7 .NOP \f\*[B-Font]tos\f[] [\f\*[B-Font]bcpollbstep\f[] \f\*[I-Font]gate\f[]] This command provides a way to delay, by the specified number of broadcast poll intervals, believing backward time steps from a broadcast server. Broadcast time networks are expected to be trusted. In the event a broadcast server's time is stepped backwards, there is clear benefit to having the clients notice this change as soon as possible. Attacks such as replay attacks can happen, however, and even though there are a number of protections built in to broadcast mode, attempts to perform a replay attack are possible. This value defaults to 0, but can be changed to any number of poll intervals between 0 and 4.
7 .NOP \f\*[B-Font]tos\f[] [\f\*[B-Font]ceiling\f[] \f\*[I-Font]ceiling\f[] | \f\*[B-Font]cohort\f[] { \f\*[B-Font]0\f[] | \f\*[B-Font]1\f[] } | \f\*[B-Font]floor\f[] \f\*[I-Font]floor\f[] | \f\*[B-Font]minclock\f[] \f\*[I-Font]minclock\f[] | \f\*[B-Font]minsane\f[] \f\*[I-Font]minsane\f[]] This command affects the clock selection and clustering algorithms. It can be used to select the quality and quantity of peers used to synchronize the system clock and is most useful in manycast mode. The variables operate as follows:
7 .NOP \f\*[B-Font]ceiling\f[] \f\*[I-Font]ceiling\f[] Peers with strata above \f\*[B-Font]ceiling\f[] will be discarded if there are at least \f\*[B-Font]minclock\f[] peers remaining. This value defaults to 15, but can be changed to any number from 1 to 15.
7 .NOP \f\*[B-Font]cohort\f[] {0 | 1 } This is a binary flag which enables (0) or disables (1) manycast server replies to manycast clients with the same stratum level. This is useful to reduce implosions where large numbers of clients with the same stratum level are present. The default is to enable these replies.
7 .NOP \f\*[B-Font]floor\f[] \f\*[I-Font]floor\f[] Peers with strata below \f\*[B-Font]floor\f[] will be discarded if there are at least \f\*[B-Font]minclock\f[] peers remaining. This value defaults to 1, but can be changed to any number from 1 to 15.
7 .NOP \f\*[B-Font]minclock\f[] \f\*[I-Font]minclock\f[] The clustering algorithm repeatedly casts out outlier associations until no more than \f\*[B-Font]minclock\f[] associations remain. This value defaults to 3, but can be changed to any number from 1 to the number of configured sources.
7 .NOP \f\*[B-Font]minsane\f[] \f\*[I-Font]minsane\f[] This is the minimum number of candidates available to the clock selection algorithm in order to produce one or more truechimers for the clustering algorithm. If fewer than this number are available, the clock is undisciplined and allowed to run free. The default is 1 for legacy purposes. However, according to principles of Byzantine agreement, \f\*[B-Font]minsane\f[] should be at least 4 in order to detect and discard a single falseticker.
7 .NOP \f\*[B-Font]ttl\f[] \f\*[I-Font]hop\f[] \f\*[I-Font]...\f[] This command specifies a list of TTL values in increasing order, up to 8 values can be specified. In manycast mode these values are used in turn in an expanding-ring search. The default is eight multiples of 32 starting at 31.
7 .NOP \f\*[B-Font]server\f[] \f[C]127.127.\f[]\f\*[I-Font]t\f[].\f\*[I-Font]u\f[] [\f\*[B-Font]prefer\f[]] [\f\*[B-Font]mode\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]minpoll\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]maxpoll\f[] \f\*[I-Font]int\f[]] This command can be used to configure reference clocks in special ways. The options are interpreted as follows:
7 .NOP \f\*[B-Font]prefer\f[] Marks the reference clock as preferred. All other things being equal, this host will be chosen for synchronization among a set of correctly operating hosts. See the "Mitigation Rules and the prefer Keyword" page (available as part of the HTML documentation provided in /usr/share/doc/ntp\f[]) for further information.
7 .NOP \f\*[B-Font]mode\f[] \f\*[I-Font]int\f[] Specifies a mode number which is interpreted in a device-specific fashion. For instance, it selects a dialing protocol in the ACTS driver and a device subtype in the parse drivers.
7 .NOP \f\*[B-Font]minpoll\f[] \f\*[I-Font]int\f[]
7 .NOP \f\*[B-Font]maxpoll\f[] \f\*[I-Font]int\f[] These options specify the minimum and maximum polling interval for reference clock messages, as a power of 2 in seconds For most directly connected reference clocks, both \f\*[B-Font]minpoll\f[] and \f\*[B-Font]maxpoll\f[] default to 6 (64 s). For modem reference clocks, \f\*[B-Font]minpoll\f[] defaults to 10 (17.1 m) and \f\*[B-Font]maxpoll\f[] defaults to 14 (4.5 h). The allowable range is 4 (16 s) to 17 (36.4 h) inclusive.
7 .NOP \f\*[B-Font]fudge\f[] \f[C]127.127.\f[]\f\*[I-Font]t\f[].\f\*[I-Font]u\f[] [\f\*[B-Font]time1\f[] \f\*[I-Font]sec\f[]] [\f\*[B-Font]time2\f[] \f\*[I-Font]sec\f[]] [\f\*[B-Font]stratum\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]refid\f[] \f\*[I-Font]string\f[]] [\f\*[B-Font]mode\f[] \f\*[I-Font]int\f[]] [\f\*[B-Font]flag1\f[] \f\*[B-Font]0\f[] \f\*[B-Font]|\f[] \f\*[B-Font]1\f[]] [\f\*[B-Font]flag2\f[] \f\*[B-Font]0\f[] \f\*[B-Font]|\f[] \f\*[B-Font]1\f[]] [\f\*[B-Font]flag3\f[] \f\*[B-Font]0\f[] \f\*[B-Font]|\f[] \f\*[B-Font]1\f[]] [\f\*[B-Font]flag4\f[] \f\*[B-Font]0\f[] \f\*[B-Font]|\f[] \f\*[B-Font]1\f[]] This command can be used to configure reference clocks in special ways. It must immediately follow the \f\*[B-Font]server\f[] command which configures the driver. Note that the same capability is possible at run time using the ntpdc\f[](@NTPDC_MS@)\f[] program. The options are interpreted as follows:
7 .NOP \f\*[B-Font]time1\f[] \f\*[I-Font]sec\f[] Specifies a constant to be added to the time offset produced by the driver, a fixed-point decimal number in seconds. This is used as a calibration constant to adjust the nominal time offset of a particular clock to agree with an external standard, such as a precision PPS signal. It also provides a way to correct a systematic error or bias due to serial port or operating system latencies, different cable lengths or receiver internal delay. The specified offset is in addition to the propagation delay provided by other means, such as internal DIPswitches. Where a calibration for an individual system and driver is available, an approximate correction is noted in the driver documentation pages. Note: in order to facilitate calibration when more than one radio clock or PPS signal is supported, a special calibration feature is available. It takes the form of an argument to the \f\*[B-Font]enable\f[] command described in Miscellaneous\f[] Options\f[] page and operates as described in the "Reference Clock Drivers" page (available as part of the HTML documentation provided in /usr/share/doc/ntp\f[]).
7 .NOP \f\*[B-Font]time2\f[] \f\*[I-Font]secs\f[] Specifies a fixed-point decimal number in seconds, which is interpreted in a driver-dependent way. See the descriptions of specific drivers in the "Reference Clock Drivers" page (available as part of the HTML documentation provided in /usr/share/doc/ntp\f[] ).\f[]
7 .NOP \f\*[B-Font]stratum\f[] \f\*[I-Font]int\f[] Specifies the stratum number assigned to the driver, an integer between 0 and 15. This number overrides the default stratum number ordinarily assigned by the driver itself, usually zero.
7 .NOP \f\*[B-Font]refid\f[] \f\*[I-Font]string\f[] Specifies an ASCII string of from one to four characters which defines the reference identifier used by the driver. This string overrides the default identifier ordinarily assigned by the driver itself.
7 .NOP \f\*[B-Font]mode\f[] \f\*[I-Font]int\f[] Specifies a mode number which is interpreted in a device-specific fashion. For instance, it selects a dialing protocol in the ACTS driver and a device subtype in the parse drivers.
7 .NOP \f\*[B-Font]flag1\f[] \f\*[B-Font]0\f[] \f\*[B-Font]|\f[] \f\*[B-Font]1\f[]
7 .NOP \f\*[B-Font]flag2\f[] \f\*[B-Font]0\f[] \f\*[B-Font]|\f[] \f\*[B-Font]1\f[]
7 .NOP \f\*[B-Font]flag3\f[] \f\*[B-Font]0\f[] \f\*[B-Font]|\f[] \f\*[B-Font]1\f[]
7 .NOP \f\*[B-Font]flag4\f[] \f\*[B-Font]0\f[] \f\*[B-Font]|\f[] \f\*[B-Font]1\f[] These four flags are used for customizing the clock driver. The interpretation of these values, and whether they are used at all, is a function of the particular clock driver. However, by convention \f\*[B-Font]flag4\f[] is used to enable recording monitoring data to the \f\*[B-Font]clockstats\f[] file configured with the \f\*[B-Font]filegen\f[] command. Further information on the \f\*[B-Font]filegen\f[] command can be found in Monitoring\f[] Options\f[].
7 .NOP \f\*[B-Font]broadcastdelay\f[] \f\*[I-Font]seconds\f[] The broadcast and multicast modes require a special calibration to determine the network delay between the local and remote servers. Ordinarily, this is done automatically by the initial protocol exchanges between the client and server. In some cases, the calibration procedure may fail due to network or server access controls, for example. This command specifies the default delay to be used under these circumstances. Typically (for Ethernet), a number between 0.003 and 0.007 seconds is appropriate. The default when this command is not used is 0.004 seconds.
7 .NOP \f\*[B-Font]calldelay\f[] \f\*[I-Font]delay\f[] This option controls the delay in seconds between the first and second packets sent in burst or iburst mode to allow additional time for a modem or ISDN call to complete.
7 .NOP \f\*[B-Font]driftfile\f[] \f\*[I-Font]driftfile\f[] This command specifies the complete path and name of the file used to record the frequency of the local clock oscillator. This is the same operation as the \f\*[B-Font]-f\f[] command line option. If the file exists, it is read at startup in order to set the initial frequency and then updated once per hour with the current frequency computed by the daemon. If the file name is specified, but the file itself does not exist, the starts with an initial frequency of zero and creates the file when writing it for the first time. If this command is not given, the daemon will always start with an initial frequency of zero. The file format consists of a single line containing a single floating point number, which records the frequency offset measured in parts-per-million (PPM). The file is updated by first writing the current drift value into a temporary file and then renaming this file to replace the old version. This implies that ntpd\f[](@NTPD_MS@)\f[] must have write permission for the directory the drift file is located in, and that file system links, symbolic or otherwise, should be avoided.
7 .NOP \f\*[B-Font]dscp\f[] \f\*[I-Font]value\f[] This option specifies the Differentiated Services Control Point (DSCP) value, a 6-bit code. The default value is 46, signifying Expedited Forwarding.
7 .NOP \f\*[B-Font]enable\f[] [\f\*[B-Font]auth\f[] | \f\*[B-Font]bclient\f[] | \f\*[B-Font]calibrate\f[] | \f\*[B-Font]kernel\f[] | \f\*[B-Font]mode7\f[] | \f\*[B-Font]monitor\f[] | \f\*[B-Font]ntp\f[] | \f\*[B-Font]stats\f[] | \f\*[B-Font]peer_clear_digest_early\f[] | \f\*[B-Font]unpeer_crypto_early\f[] | \f\*[B-Font]unpeer_crypto_nak_early\f[] | \f\*[B-Font]unpeer_digest_early\f[]]
7 .NOP \f\*[B-Font]disable\f[] [\f\*[B-Font]auth\f[] | \f\*[B-Font]bclient\f[] | \f\*[B-Font]calibrate\f[] | \f\*[B-Font]kernel\f[] | \f\*[B-Font]mode7\f[] | \f\*[B-Font]monitor\f[] | \f\*[B-Font]ntp\f[] | \f\*[B-Font]stats\f[] | \f\*[B-Font]peer_clear_digest_early\f[] | \f\*[B-Font]unpeer_crypto_early\f[] | \f\*[B-Font]unpeer_crypto_nak_early\f[] | \f\*[B-Font]unpeer_digest_early\f[]] Provides a way to enable or disable various server options. Flags not mentioned are unaffected. Note that all of these flags can be controlled remotely using the ntpdc\f[](@NTPDC_MS@)\f[] utility program.
7 .NOP \f\*[B-Font]auth\f[] Enables the server to synchronize with unconfigured peers only if the peer has been correctly authenticated using either public key or private key cryptography. The default for this flag is \f\*[B-Font]enable\f[].
7 .NOP \f\*[B-Font]bclient\f[] Enables the server to listen for a message from a broadcast or multicast server, as in the \f\*[B-Font]multicastclient\f[] command with default address. The default for this flag is \f\*[B-Font]disable\f[].
7 .NOP \f\*[B-Font]calibrate\f[] Enables the calibrate feature for reference clocks. The default for this flag is \f\*[B-Font]disable\f[].
7 .NOP \f\*[B-Font]kernel\f[] Enables the kernel time discipline, if available. The default for this flag is \f\*[B-Font]enable\f[] if support is available, otherwise \f\*[B-Font]disable\f[].
7 .NOP \f\*[B-Font]mode7\f[] Enables processing of NTP mode 7 implementation-specific requests which are used by the deprecated ntpdc\f[](@NTPDC_MS@)\f[] program. The default for this flag is disable. This flag is excluded from runtime configuration using ntpq\f[](@NTPQ_MS@)\f[]. The ntpq\f[](@NTPQ_MS@)\f[] program provides the same capabilities as ntpdc\f[](@NTPDC_MS@)\f[] using standard mode 6 requests.
7 .NOP \f\*[B-Font]monitor\f[] Enables the monitoring facility. See the ntpdc\f[](@NTPDC_MS@)\f[] program and the \f\*[B-Font]monlist\f[] command or further information. The default for this flag is \f\*[B-Font]enable\f[].
7 .NOP \f\*[B-Font]ntp\f[] Enables time and frequency discipline. In effect, this switch opens and closes the feedback loop, which is useful for testing. The default for this flag is \f\*[B-Font]enable\f[].
7 .NOP \f\*[B-Font]peer_clear_digest_early\f[] By default, if ntpd\f[](@NTPD_MS@)\f[] is using autokey and it receives a crypto-NAK packet that passes the duplicate packet and origin timestamp checks the peer variables are immediately cleared. While this is generally a feature as it allows for quick recovery if a server key has changed, a properly forged and appropriately delivered crypto-NAK packet can be used in a DoS attack. If you have active noticable problems with this type of DoS attack then you should consider disabling this option. You can check your \f\*[B-Font]peerstats\f[] file for evidence of any of these attacks. The default for this flag is \f\*[B-Font]enable\f[].
7 .NOP \f\*[B-Font]stats\f[] Enables the statistics facility. See the Monitoring\f[] Options\f[] section for further information. The default for this flag is \f\*[B-Font]disable\f[].
7 .NOP \f\*[B-Font]unpeer_crypto_early\f[] By default, if ntpd\f[](@NTPD_MS@)\f[] receives an autokey packet that fails TEST9, a crypto failure, the association is immediately cleared. This is almost certainly a feature, but if, in spite of the current recommendation of not using autokey, you are still using autokey and you are seeing this sort of DoS attack disabling this flag will delay tearing down the association until the reachability counter becomes zero. You can check your \f\*[B-Font]peerstats\f[] file for evidence of any of these attacks. The default for this flag is \f\*[B-Font]enable\f[].
7 .NOP \f\*[B-Font]unpeer_crypto_nak_early\f[] By default, if ntpd\f[](@NTPD_MS@)\f[] receives a crypto-NAK packet that passes the duplicate packet and origin timestamp checks the association is immediately cleared. While this is generally a feature as it allows for quick recovery if a server key has changed, a properly forged and appropriately delivered crypto-NAK packet can be used in a DoS attack. If you have active noticable problems with this type of DoS attack then you should consider disabling this option. You can check your \f\*[B-Font]peerstats\f[] file for evidence of any of these attacks. The default for this flag is \f\*[B-Font]enable\f[].
7 .NOP \f\*[B-Font]unpeer_digest_early\f[] By default, if ntpd\f[](@NTPD_MS@)\f[] receives what should be an authenticated packet that passes other packet sanity checks but contains an invalid digest the association is immediately cleared. While this is generally a feature as it allows for quick recovery, if this type of packet is carefully forged and sent during an appropriate window it can be used for a DoS attack. If you have active noticable problems with this type of DoS attack then you should consider disabling this option. You can check your \f\*[B-Font]peerstats\f[] file for evidence of any of these attacks. The default for this flag is \f\*[B-Font]enable\f[].
7 .NOP \f\*[B-Font]includefile\f[] \f\*[I-Font]includefile\f[] This command allows additional configuration commands to be included from a separate file. Include files may be nested to a depth of five; upon reaching the end of any include file, command processing resumes in the previous configuration file. This option is useful for sites that run ntpd\f[](@NTPD_MS@)\f[] on multiple hosts, with (mostly) common options (e.g., a restriction list).
7 .NOP \f\*[B-Font]interface\f[] [\f\*[B-Font]listen\f[] | \f\*[B-Font]ignore\f[] | \f\*[B-Font]drop\f[]] [\f\*[B-Font]all\f[] | \f\*[B-Font]ipv4\f[] | \f\*[B-Font]ipv6\f[] | \f\*[B-Font]wildcard\f[] \f\*[I-Font]name\f[] | \f\*[I-Font]address\f[] [\f\*[B-Font]/\f[] \f\*[I-Font]prefixlen\f[]]] The \f\*[B-Font]interface\f[] directive controls which network addresses ntpd\f[](@NTPD_MS@)\f[] opens, and whether input is dropped without processing. The first parameter determines the action for addresses which match the second parameter. The second parameter specifies a class of addresses, or a specific interface name, or an address. In the address case, \f\*[I-Font]prefixlen\f[] determines how many bits must match for this rule to apply. \f\*[B-Font]ignore\f[] prevents opening matching addresses, \f\*[B-Font]drop\f[] causes ntpd\f[](@NTPD_MS@)\f[] to open the address and drop all received packets without examination. Multiple \f\*[B-Font]interface\f[] directives can be used. The last rule which matches a particular address determines the action for it. \f\*[B-Font]interface\f[] directives are disabled if any \f\*[B-Font]-I\f[], \f\*[B-Font]--interface\f[], \f\*[B-Font]-L\f[], or \f\*[B-Font]--novirtualips\f[] command-line options are specified in the configuration file, all available network addresses are opened. The \f\*[B-Font]nic\f[] directive is an alias for \f\*[B-Font]interface\f[].
7 .NOP \f\*[B-Font]leapfile\f[] \f\*[I-Font]leapfile\f[] This command loads the IERS leapseconds file and initializes the leapsecond values for the next leapsecond event, leapfile expiration time, and TAI offset. The file can be obtained directly from the IERS at \f[C]https://hpiers.obspm.fr/iers/bul/bulc/ntp/leap-seconds.list\f[] or \f[C]ftp://hpiers.obspm.fr/iers/bul/bulc/ntp/leap-seconds.list\f[]. The \f\*[B-Font]leapfile\f[] is scanned when ntpd\f[](@NTPD_MS@)\f[] processes the \f\*[B-Font]leapfile\f[] \f\*[B-Font]directive\f[] \f\*[B-Font]or\f[] \f\*[B-Font]when\f[] \f\*[B-Font]ntpd\f[] \f\*[B-Font]detects\f[] \f\*[B-Font]that\f[] \f\*[B-Font]the\f[] \f\*[I-Font]leapfile\f[] has changed. \f\*[B-Font]ntpd\f[] checks once a day to see if the \f\*[I-Font]leapfile\f[] has changed. The update-leap\f[](1update_leapmdoc)\f[] script can be run to see if the \f\*[I-Font]leapfile\f[] should be updated.
7 .NOP \f\*[B-Font]leapsmearinterval\f[] \f\*[I-Font]seconds\f[] This EXPERIMENTAL option is only available if ntpd\f[](@NTPD_MS@)\f[] was built with the \f\*[B-Font]--enable-leap-smear\f[] option to the \f\*[B-Font]configure\f[] script. It specifies the interval over which a leap second correction will be applied. Recommended values for this option are between 7200 (2 hours) and 86400 (24 hours). .Sy DO NOT USE THIS OPTION ON PUBLIC-ACCESS SERVERS! See http://bugs.ntp.org/2855 for more information.
7 .NOP \f\*[B-Font]logconfig\f[] \f\*[I-Font]configkeyword\f[] This command controls the amount and type of output written to the system syslog\f[](3)\f[] facility or the alternate \f\*[B-Font]logfile\f[] log file. By default, all output is turned on. All \f\*[I-Font]configkeyword\f[] keywords can be prefixed with \[oq]=\[cq], \[oq]+\[cq] and \[oq]-\[cq], where \[oq]=\[cq] sets the syslog\f[](3)\f[] priority mask, \[oq]+\[cq] adds and \[oq]-\[cq] removes messages. syslog\f[](3)\f[] messages can be controlled in four classes (\f\*[B-Font]clock\f[], \f\*[B-Font]peer\f[], \f\*[B-Font]sys\f[] and \f\*[B-Font]sync\f[]). Within these classes four types of messages can be controlled: informational messages (\f\*[B-Font]info\f[]), event messages (\f\*[B-Font]events\f[]), statistics messages (\f\*[B-Font]statistics\f[]) and status messages (\f\*[B-Font]status\f[]). Configuration keywords are formed by concatenating the message class with the event class. The \f\*[B-Font]all\f[] prefix can be used instead of a message class. A message class may also be followed by the \f\*[B-Font]all\f[] keyword to enable/disable all messages of the respective message class. Thus, a minimal log configuration could look like this:
logconfig =syncstatus +syseventsThis would just list the synchronizations state of ntpd\f[](@NTPD_MS@)\f[] and the major system events. For a simple reference server, the following minimum message configuration could be useful:
logconfig =syncall +clockallThis configuration will list all clock information and synchronization information. All other events and messages about peers, system events and so on is suppressed.
7 .NOP \f\*[B-Font]logfile\f[] \f\*[I-Font]logfile\f[] This command specifies the location of an alternate log file to be used instead of the default system syslog\f[](3)\f[] facility. This is the same operation as the \f\*[B-Font]-l\f[] command line option.
7 .NOP \f\*[B-Font]mru\f[] [\f\*[B-Font]maxdepth\f[] \f\*[I-Font]count\f[] | \f\*[B-Font]maxmem\f[] \f\*[I-Font]kilobytes\f[] | \f\*[B-Font]mindepth\f[] \f\*[I-Font]count\f[] | \f\*[B-Font]maxage\f[] \f\*[I-Font]seconds\f[] | \f\*[B-Font]initialloc\f[] \f\*[I-Font]count\f[] | \f\*[B-Font]initmem\f[] \f\*[I-Font]kilobytes\f[] | \f\*[B-Font]incalloc\f[] \f\*[I-Font]count\f[] | \f\*[B-Font]incmem\f[] \f\*[I-Font]kilobytes\f[]] Controls size limite of the monitoring facility's Most Recently Used (MRU) list of client addresses, which is also used by the rate control facility.
7 .NOP \f\*[B-Font]maxdepth\f[] \f\*[I-Font]count\f[]
7 .NOP \f\*[B-Font]maxmem\f[] \f\*[I-Font]kilobytes\f[] Equivalent upper limits on the size of the MRU list, in terms of entries or kilobytes. The acutal limit will be up to \f\*[B-Font]incalloc\f[] entries or \f\*[B-Font]incmem\f[] kilobytes larger. As with all of the \f\*[B-Font]mru\f[] options offered in units of entries or kilobytes, if both \f\*[B-Font]maxdepth\f[] and \f\*[B-Font]maxmem\f[] \f\*[B-Font]are\f[] \f\*[B-Font]used,\f[] \f\*[B-Font]the\f[] \f\*[B-Font]last\f[] \f\*[B-Font]one\f[] \f\*[B-Font]used\f[] \f\*[B-Font]controls.\f[] The default is 1024 kilobytes.
7 .NOP \f\*[B-Font]mindepth\f[] \f\*[I-Font]count\f[] Lower limit on the MRU list size. When the MRU list has fewer than \f\*[B-Font]mindepth\f[] entries, existing entries are never removed to make room for newer ones, regardless of their age. The default is 600 entries.
7 .NOP \f\*[B-Font]maxage\f[] \f\*[I-Font]seconds\f[] Once the MRU list has \f\*[B-Font]mindepth\f[] entries and an additional client is to ba added to the list, if the oldest entry was updated more than \f\*[B-Font]maxage\f[] seconds ago, that entry is removed and its storage is reused. If the oldest entry was updated more recently the MRU list is grown, subject to \f\*[B-Font]maxdepth\f[] \f\*[B-Font]/\f[] \f\*[B-Font]moxmem\f[]. The default is 64 seconds.
7 .NOP \f\*[B-Font]initalloc\f[] \f\*[I-Font]count\f[]
7 .NOP \f\*[B-Font]initmem\f[] \f\*[I-Font]kilobytes\f[] Initial memory allocation at the time the monitoringfacility is first enabled, in terms of the number of entries or kilobytes. The default is 4 kilobytes.
7 .NOP \f\*[B-Font]incalloc\f[] \f\*[I-Font]count\f[]
7 .NOP \f\*[B-Font]incmem\f[] \f\*[I-Font]kilobytes\f[] Size of additional memory allocations when growing the MRU list, in entries or kilobytes. The default is 4 kilobytes.
7 .NOP \f\*[B-Font]nonvolatile\f[] \f\*[I-Font]threshold\f[] Specify the \f\*[I-Font]threshold\f[] delta in seconds before an hourly change to the \f\*[B-Font]driftfile\f[] (frequency file) will be written, with a default value of 1e-7 (0.1 PPM). The frequency file is inspected each hour. If the difference between the current frequency and the last value written exceeds the threshold, the file is written and the \f\*[B-Font]threshold\f[] becomes the new threshold value. If the threshold is not exceeeded, it is reduced by half. This is intended to reduce the number of file writes for embedded systems with nonvolatile memory.
7 .NOP \f\*[B-Font]phone\f[] \f\*[I-Font]dial\f[] \f\*[I-Font]...\f[] This command is used in conjunction with the ACTS modem driver (type 18) or the JJY driver (type 40, mode 100 - 180). For the ACTS modem driver (type 18), the arguments consist of a maximum of 10 telephone numbers used to dial USNO, NIST, or European time service. For the JJY driver (type 40 mode 100 - 180), the argument is one telephone number used to dial the telephone JJY service. The Hayes command ATDT is normally prepended to the number. The number can contain other modem control codes as well.
7 .NOP \f\*[B-Font]reset\f[] [\f\*[B-Font]allpeers\f[]] [\f\*[B-Font]auth\f[]] [\f\*[B-Font]ctl\f[]] [\f\*[B-Font]io\f[]] [\f\*[B-Font]mem\f[]] [\f\*[B-Font]sys\f[]] [\f\*[B-Font]timer\f[]] Reset one or more groups of counters maintained by \f\*[B-Font]ntpd\f[] and exposed by \f\*[B-Font]ntpq\f[] and \f\*[B-Font]ntpdc\f[].
7 .NOP \f\*[B-Font]rlimit\f[] [\f\*[B-Font]memlock\f[] \f\*[I-Font]Nmegabytes\f[] | \f\*[B-Font]stacksize\f[] \f\*[I-Font]N4kPages\f[] \f\*[B-Font]filenum\f[] \f\*[I-Font]Nfiledescriptors\f[]]
7 .NOP \f\*[B-Font]memlock\f[] \f\*[I-Font]Nmegabytes\f[] Specify the number of megabytes of memory that should be allocated and locked. Probably only available under Linux, this option may be useful when dropping root (the \f\*[B-Font]-i\f[] option). The default is 32 megabytes on non-Linux machines, and -1 under Linux. -1 means "do not lock the process into memory". 0 means "lock whatever memory the process wants into memory".
7 .NOP \f\*[B-Font]stacksize\f[] \f\*[I-Font]N4kPages\f[] Specifies the maximum size of the process stack on systems with the mlockall\f[]()\f[] function. Defaults to 50 4k pages (200 4k pages in OpenBSD).
7 .NOP \f\*[B-Font]filenum\f[] \f\*[I-Font]Nfiledescriptors\f[] Specifies the maximum number of file descriptors ntpd may have open at once. Defaults to the system default.
7 .NOP \f\*[B-Font]saveconfigdir\f[] \f\*[I-Font]directory_path\f[] Specify the directory in which to write configuration snapshots requested with .Cm ntpq 's \f\*[B-Font]saveconfig\f[] command. If \f\*[B-Font]saveconfigdir\f[] does not appear in the configuration file, \f\*[B-Font]saveconfig\f[] requests are rejected by \f\*[B-Font]ntpd\f[].
7 .NOP \f\*[B-Font]saveconfig\f[] \f\*[I-Font]filename\f[] Write the current configuration, including any runtime modifications given with \f\*[B-Font]:config\f[] or \f\*[B-Font]config-from-file\f[] to the \f\*[B-Font]ntpd\f[] host's \f\*[I-Font]filename\f[] in the \f\*[B-Font]saveconfigdir\f[]. This command will be rejected unless the \f\*[B-Font]saveconfigdir\f[] directive appears in .Cm ntpd 's configuration file. \f\*[I-Font]filename\f[] can use strftime\f[](3)\f[] format directives to substitute the current date and time, for example, \f\*[B-Font]saveconfig ntp-%Y%m%d-%H%M%S.conf\f[]. The filename used is stored in the system variable \f\*[B-Font]savedconfig\f[]. Authentication is required.
7 .NOP \f\*[B-Font]setvar\f[] \f\*[I-Font]variable\f[] [\f\*[B-Font]default\f[]] This command adds an additional system variable. These variables can be used to distribute additional information such as the access policy. If the variable of the form name\f[]=\f[]\f\*[I-Font]value\f[] is followed by the \f\*[B-Font]default\f[] keyword, the variable will be listed as part of the default system variables (ntpq\f[](@NTPQ_MS@)\f[] \f\*[B-Font]rv\f[] command)). These additional variables serve informational purposes only. They are not related to the protocol other that they can be listed. The known protocol variables will always override any variables defined via the \f\*[B-Font]setvar\f[] mechanism. There are three special variables that contain the names of all variable of the same group. The sys_var_list\f[] holds the names of all system variables. The peer_var_list\f[] holds the names of all peer variables and the clock_var_list\f[] holds the names of the reference clock variables.
7 .NOP \f\*[B-Font]sysinfo\f[] Display operational summary.
7 .NOP \f\*[B-Font]sysstats\f[] Show statistics counters maintained in the protocol module.
7 .NOP \f\*[B-Font]tinker\f[] [\f\*[B-Font]allan\f[] \f\*[I-Font]allan\f[] | \f\*[B-Font]dispersion\f[] \f\*[I-Font]dispersion\f[] | \f\*[B-Font]freq\f[] \f\*[I-Font]freq\f[] | \f\*[B-Font]huffpuff\f[] \f\*[I-Font]huffpuff\f[] | \f\*[B-Font]panic\f[] \f\*[I-Font]panic\f[] | \f\*[B-Font]step\f[] \f\*[I-Font]step\f[] | \f\*[B-Font]stepback\f[] \f\*[I-Font]stepback\f[] | \f\*[B-Font]stepfwd\f[] \f\*[I-Font]stepfwd\f[] | \f\*[B-Font]stepout\f[] \f\*[I-Font]stepout\f[]] This command can be used to alter several system variables in very exceptional circumstances. It should occur in the configuration file before any other configuration options. The default values of these variables have been carefully optimized for a wide range of network speeds and reliability expectations. In general, they interact in intricate ways that are hard to predict and some combinations can result in some very nasty behavior. Very rarely is it necessary to change the default values; but, some folks cannot resist twisting the knobs anyway and this command is for them. Emphasis added: twisters are on their own and can expect no help from the support group. The variables operate as follows:
7 .NOP \f\*[B-Font]allan\f[] \f\*[I-Font]allan\f[] The argument becomes the new value for the minimum Allan intercept, which is a parameter of the PLL/FLL clock discipline algorithm. The value in log2 seconds defaults to 7 (1024 s), which is also the lower limit.
7 .NOP \f\*[B-Font]dispersion\f[] \f\*[I-Font]dispersion\f[] The argument becomes the new value for the dispersion increase rate, normally .000015 s/s.
7 .NOP \f\*[B-Font]freq\f[] \f\*[I-Font]freq\f[] The argument becomes the initial value of the frequency offset in parts-per-million. This overrides the value in the frequency file, if present, and avoids the initial training state if it is not.
7 .NOP \f\*[B-Font]huffpuff\f[] \f\*[I-Font]huffpuff\f[] The argument becomes the new value for the experimental huff-n'-puff filter span, which determines the most recent interval the algorithm will search for a minimum delay. The lower limit is 900 s (15 m), but a more reasonable value is 7200 (2 hours). There is no default, since the filter is not enabled unless this command is given.
7 .NOP \f\*[B-Font]panic\f[] \f\*[I-Font]panic\f[] The argument is the panic threshold, normally 1000 s. If set to zero, the panic sanity check is disabled and a clock offset of any value will be accepted.
7 .NOP \f\*[B-Font]step\f[] \f\*[I-Font]step\f[] The argument is the step threshold, which by default is 0.128 s. It can be set to any positive number in seconds. If set to zero, step adjustments will never occur. Note: The kernel time discipline is disabled if the step threshold is set to zero or greater than the default.
7 .NOP \f\*[B-Font]stepback\f[] \f\*[I-Font]stepback\f[] The argument is the step threshold for the backward direction, which by default is 0.128 s. It can be set to any positive number in seconds. If both the forward and backward step thresholds are set to zero, step adjustments will never occur. Note: The kernel time discipline is disabled if each direction of step threshold are either set to zero or greater than .5 second.
7 .NOP \f\*[B-Font]stepfwd\f[] \f\*[I-Font]stepfwd\f[] As for stepback, but for the forward direction.
7 .NOP \f\*[B-Font]stepout\f[] \f\*[I-Font]stepout\f[] The argument is the stepout timeout, which by default is 900 s. It can be set to any positive number in seconds. If set to zero, the stepout pulses will not be suppressed.
7 .NOP \f\*[B-Font]writevar\f[] \f\*[I-Font]assocID name\f[] \f\*[I-Font]=\f[] \f\*[I-Font]value\f[] \f\*[I-Font][,...]\f[] Write (create or update) the specified variables. If the \f\*[B-Font]assocID\f[] is zero, the variablea re from the system variables name space, otherwise they are from the peer variables name space. The \f\*[B-Font]assocID\f[] is required, as the same name can occur in both name spaces.
7 .NOP \f\*[B-Font]trap\f[] \f\*[I-Font]host_address\f[] [\f\*[B-Font]port\f[] \f\*[I-Font]port_number\f[]] [\f\*[B-Font]interface\f[] \f\*[I-Font]interface_address\f[]] This command configures a trap receiver at the given host address and port number for sending messages with the specified local interface address. If the port number is unspecified, a value of 18447 is used. If the interface address is not specified, the message is sent with a source address of the local interface the message is sent through. Note that on a multihomed host the interface used may vary from time to time with routing changes.
7 .NOP \f\*[B-Font]ttl\f[] \f\*[I-Font]hop\f[] \f\*[I-Font]...\f[] This command specifies a list of TTL values in increasing order. Up to 8 values can be specified. In \f\*[B-Font]manycast\f[] mode these values are used in-turn in an expanding-ring search. The default is eight multiples of 32 starting at 31. The trap receiver will generally log event messages and other information from the server in a log file. While such monitor programs may also request their own trap dynamically, configuring a trap receiver will ensure that no messages are lost when the server is started.
7 .NOP \f\*[B-Font]hop\f[] \f\*[I-Font]...\f[] This command specifies a list of TTL values in increasing order, up to 8 values can be specified. In manycast mode these values are used in turn in an expanding-ring search. The default is eight multiples of 32 starting at 31.
.NOP \f\*[B-Font]--help\f[] Display usage information and exit.
.NOP \f\*[B-Font]--more-help\f[] Pass the extended usage information through a pager.
.NOP \f\*[B-Font]--version\f[] [{\f\*[I-Font]v|c|n\f[]}] Output version of program and exit. The default mode is `v', a simple version. The `c' mode will print copyright information and `n' will print the full copyright notice.
NTP_CONF_<option-name> or NTP_CONF
15 .NOP /etc/ntp.conf\f[] the default name of the configuration file
.ns
15 .NOP ntp.keys\f[] private MD5 keys
.ns
15 .NOP ntpkey\f[] RSA private key
.ns
15 .NOP ntpkey_\f[]\f\*[I-Font]host\f[] RSA public key
.ns
15 .NOP ntp_dh\f[] Diffie-Hellman agreement parameters
.NOP 0 " (EXIT_SUCCESS)" Successful program execution.
.NOP 1 " (EXIT_FAILURE)" The operation failed or the command syntax was not valid.
.NOP 70 " (EX_SOFTWARE)" libopts had an internal operational error. Please report it to autogen-users@lists.sourceforge.net. Thank you.